Primary hepatoid adenocarcinoma of lung: A rare malignancy mimicking tuberculosis

Hepatoid adenocarcinoma of lung (HAL) is a rare aggressive malignant tumour which histologically resembles hepatocellular carcinoma (HCC). Hepatoid adenocarcinoma (HAC) mostly produces high levels of alphafetoprotein (AFP) and is frequently found in extrahepatic organs including stomach, testes, ovaries, lungs and pancreas. Our patient was a male in his 40s with a chronic smoking history, presented with complaints of fever, weight loss, cough and anorexia for one month. On the basis of history, examination and initial investigation patient were started on empirical antitubercular therapy. However, within a span of 10 days, patient's condition worsened, and he developed a pulmonary embolism, which despite adequate treatment did not improve and the patient succumbed to his illness. Postmortem biopsy revealed a rare primary lung tumour, HAL.

A case report of pulmonary hepatoid adenocarcinoma: promoting standardized diagnosis and treatment of the rare disease

Objective

To investigate the clinical features, pathological characteristics, immunophenotype, differential diagnosis and prognosis of pulmonary hepatoid adenocarcinoma using a clinical case and literature report.

Methods

We analyzed the clinical presentation, histological pattern and immunohistochemistry of a case of primary hepatoid adenocarcinoma of the lung in April 2022. We also reviewed literature on hepatoid adenocarcinoma of the lung from PubMed database.

Results

The patient was a 65-year-old male with smoking history, who was admitted to hospital with an enlarged axillary lymph node. The mass was round, hard, and grayish-white and grayish-yellow in color. Microscopically, it presented hepatocellular carcinoma-like and adenocarcinoma differentiation features, with abundant blood sinuses visible in the interstitium. Immunohistochemistry showed that the tumor cells were positive for hepatocyte markers, including AFP, TTF-1, CK7 and villin, and negative for CK5/6, CD56, GATA3, CEA and vimentin.

Conclusion

Pulmonary hepatoid adenocarcinoma is a rare epithelial malignancy of primary origin in the lung with poor prognosis. Establishing the diagnosis relies mainly on the detection of hepatocellular structural morphology resembling hepatocellular carcinoma, and on clinicopathological and immunohistochemical testing to exclude diseases such as hepatocellular carcinoma. Combination treatment, mainly surgery, can prolong the survival of early-stage cases of the disease, whereas radiotherapy is mostly used for intermediate and advanced cases. Individualized treatment with molecular-targeted drugs and immunotherapy has shown different therapeutic effects for different patients. Further research is needed to better understand this rare clinical condition for the development and optimization of treatment strategies.

Primary pulmonary hepatoid adenocarcinoma: A case report and review of the literature

RATIONALE

Hepatoid adenocarcinoma of lung (HAL) is a rare malignant tumor, which can be defined as a primary alpha-fetoprotein (AFP)-producing lung carcinoma. The majority of hepatoid adenocarcinoma (HAC) expressed AFP in tumor cells, but AFP expression is not required for its diagnosis according to the modified diagnostic criteria. Despite that HAC exhibits a poor prognosis and ineffective treatment options, early diagnosis and aggressive treatment can result in long-term survival.

PATIENT CONCERNS

We report a 70-year-old Chinese male patient with alcoholic intake over 30 years and smoking history of 60 cigarettes per day for 40 years. He sought medical consultation for productive cough and hemoptysis sputum.

DIAGNOSES AND INTERVENTIONS

Chest CT scan revealed a mass (6.4 × 5.5 cm) in the left lower lobe of the lung. The patient underwent curative surgical resection, and subsequently diagnosed as HAL.

OUTCOMES

Eighteen months after primary diagnosis, the patient died of multiple organ failure caused by distant metastases.

LESSONS

Familiarizing with the clinical features and modified diagnostic criteria of this rare tumor may increase awareness of the disease among clinicians and pathologists, thereby avoiding misdiagnosis and mistreatment.

Hepatoid adenocarcinoma of the lung: Review of a rare form of lung cancer

RATIONALE

Hepatoid adenocarcinoma (HAC) is a rare malignant lung tumor that histologically resembles typical hepatocellular carcinoma (HCC) when it is metastatic to the lung. To date, this clinical entity has not been highlighted in the pulmonary literature.

OBJECTIVE

We present a review of all known cases of HAC, including the relevant clinical and histopathological features important for pulmonologists.

MEASUREMENTS AND MAIN RESULTS

The purpose of this report is to present a new case of HAC, with typical clinical and histologic features of this malignancy, and to summarize findings of previously reported cases. A systematic literature search of the electronic database PUBMED was conducted to identify all cases of hepatoid adenocarcinoma reported in the English literature, between January 1980 and June 2015. HAC and HCC can be distinguished by immunohistochemical staining. HAC usually presents as a large bulky solitary mass in the upper lobe; there is an exceedingly high prevalence in males and most patients with this tumor are smokers. Serum alpha-fetoprotein (AFP) in very high levels has been a distinguishing feature of this tumor. Nodal and distant metastases are common at initial presentation and, as a result, the prognosis is very poor. Resection and long-term survival, however, have been reported.

CONCLUSION

Hepatoid adenocarcinoma, first described as a gastric tumor, has also been described in the lung. It morphologically resembles and must be distinguished from metastatic HCC of the lung. While most tumors produce AFP, the case we present demonstrates that this should not be a criterion for diagnosis.

Adult hepatic cavernous hemangioma with highly elevated α-fetoprotein: A case report and review of the literature

A 47-year-old male presented with a six-month history of fatigue and a four-month history of alanine and aspartate aminopherase elevation. Laboratory examination revealed that the serum α-fetoprotein (AFP) level was 371.51 μg/l (normal range, 0–20 μg/l), and a computed tomography scan revealed a hypodense lesion in the left hepatic lobe. During laparotomy, a dark red-colored soft tumor (1.5×1.7 cm in diameter) was found in segment eight of the liver. Intra-operative pathology and post-operative histopathology examinations revealed that the tumor was a hepatic cavernous hemangioma. The serum AFP level was decreased to 24.45 μg/l by the second post-operative week. The literature was searched and only three similar cases were found. A brief review of this rare disease entity was produced, which attempted to explain this appearance reasonably.